Power takeoff grinder

ABSTRACT

AN IMPROVED GRINDER SECURED TO THE POWER TAKEOFF OF A TRACTOR, THE GRINDER UNIT ALSO INCLUDING A STUB SHAFT FOR POSITIONING A GRINDING WHEEL A RELATIVELY FAR DISTANCE FROM A BEARING OF THE POWDER TAKEOFF SHAFT WHERE GRINDING WORK IS READILY MORE ACCESSIBLE, AND THE ASSEMBLY ALSO INCLUDING A SLEEVE POSITIONED ADJACENT A SHOULDER OF THE STUB SHAFT AND A PLURALITY OF WASHERS POSITIONED ADJACENT ONE END OF THE SLEEVE, THE GRINDER DISC BEING SECURED BETWEEN A   PAIR OF SPRING LOCK WASHERS AND RETAINED BY A THUMB SCREW SECURED IN THE END OF THE STUB SHAFT.

Nov. 23, 1971 w. HusAcK 3,621,621

POWER TAKEOFF GRINDER Filed Aug 25, 1969 //v VE/V r012 la/z 4 07M MUS/76K United States Patent 3,621,621 POWER TAKEOFF GRINDER William Husack, Box 130, Calder, Saskatchewan, Canada Filed Aug. 25, 1969, Ser. No. 852,737 Int. Cl. B24b 19/00, 41/00 US. Cl. 51-258 ABSTRACT OF THE DISCLOSURE 2 Claims This invention relates generally to grinding devices.

A principal object of the preesnt invention is to provide a grinding unit secured to a power takeoff of a tractor and which is an improvement of applicants earlier design.

Another object of the present invention is to provide a power takeoff grinder wherein the assembly incorporates a stub shaft so as to position the grinding disc a sufficient distance from the tractor power takeoff where the disc is more serviceable for use on different shaped objects.

Yet another object of the present invention is to provide a power takeoff grinder wherein one end of the stub shaft is secured removeably over a power take-off shaft of the tractor while the opposite end of the stub shaft has the grinding unit secured thereto.

Other objects of the present invention are to provide a power takeoff grinder which is simple in design, inexpensive to fnanufacture, rugged in construction, easy to use and efficient in operation.

These and other objects will become readily evident upon a study of the following specification and the accompanying drawing wherein:

FIG. 1 is a side eleva'ion view of the present invention shown partly in cross section and mounted upon a power takeoff of a tractor.

FIG. 2 is a side elevation view of the stub shaft shown per se,

FIG. 3 is a perspective view of an interlocking washer, and

FIG. 4 is a perspective view of a spring lock washer.

Referring now to the drawing in detail, the reference numeral represents a power takeoff grinder according to the present invention wherein there is a stub shaft 11 having a diametrically enlarged portion 12 at one end thereof and a relatively diametrically smaller extending shank 13 forming the opposite end.

The portion 12 has a central opening 14 there within extending from an end wall 15, the opening 14 being adaptable for receiving the power takeoff shaft of a tractor 17.

A pair of threaded openings 18 through the side Wall of the portion 12 is adaptable for receiving a pair of set screws 19 for temporarily securing the stub shaft to the power takeoff shaft 16.

The shank 13 of the stub shaft 11 receives a sleeve 20 which on one end wall 21 is provided with a cross shaped recess 22, the opposite end Wall 23 of the sleeve 20 being flush throughout so to form a safety clutch slipping means.

A plurality of washers 24 are each formed with a 3,621,621 Patented Nov. 23, 1971 cross-shaped recess 25 on one face thereof and a cross shaped rib 26 on the opposite face thereof and adapted to engage the recesses of a preceding adjacent washer, thus permitting a thorough locking means together and providing a ready adjustment means for placement of a grinder disc 27 in a desired position along the shank 13 of the stub shaft 11.

On each side of the grinding disc 27, a spring lock washer 28 is located, each spring lock washer 28 being formed with opposed lugs 29 bent at right angles to the body thereof for frictionally engaging the grinding disc 27.

A common flat washer 30 is mounted over the outer spring lock washer and a thumb screw 31 compresses the Whole together in order to prevent the grinding disc from rotating freely upon the stub shaft.

It will now be readily apparent that in operative use that the flush face 23 of the sleeve 20 forms a safety clutch slipping means in the event the grinding disc 27 becomes jammed while in operation, and which is adapted to bear against the shoulder 32 of the stub shaft.

It will now be apparent that this attachment can be mounted quickly, is portable being mounted right on the tractor, can receive a relatively large grinding wheel and which has considerable power available from the tractor directly.

The power takeoff grinder is readily serviceable for sharpening cultivator shovels, axes, chisels, plowshares, discer blades, disc blades, and the like.

The present power takeoff grinder would readily fit a greater number of tractors as not every power takeoff shaft has an opening drilled and tapped on the end thereof.

To mount, slip the power takeoff grinder complete with stub shaft onto the tractor power takeoff shaft and tighten the two set screws. To remove, merely loosen the set screws and pull the entire assembly off. The grinding wheel due to the stub shaft would extend further to the rear of the tractor and be more convenient to work.

Tractors that are already provided with an opening on the end of the power takeoff shaft will find the stub shaft an optional feature.

I claim:

1. In a power takeoff grinder, the combination of an assembly including a means for grinding a grinding disc, means for rotating said disc, and means for selectively positioning said disc at a desired position relative to a power takeoff shaft of a tractor, said positioning means comprising a stub shaft, said stub shaft having a diametrically enlarged portion at one end thereof and an extending shank forming the opposite end thereof, said diametrically enlarged portion having an opening extending thereinto from an end Wall of said stub shaft, said opening being adaptable for receiving a power takeoff shaft of said tractor, and a plurality of threaded openings through a cylindrical side wall of said diametrically enlarged portion, said threaded opening receiving a pair of set screws for selective engagement of said stub shaft upon said power takeoff shaft, a cylindrical sleeve being mounted upon said shank of said stub shaft, said sleeve being positioned adjacent a shoulder formed on said stub shaft between said diametrically enlarged portion and said shank, one end of said sleeve positioned adjacent said shoulder being flush while an opposite end of aid sleeve is provided with a cross-shaped recess, a plurality of washers being mounted upon said shank of said stub shaft and adjacent said sleeve, each said washer being formed with a cross-shaped recess on one face thereof and a cross-shaped rib on an opposite face thereof, said ribs of each said washer being adaptable for engaging the recesses of adjacent washers, thus permitting a thorough locking means therebetween.

2. The combination as set forth in claim 1, wherein said grinding disc is positioned upon said shank of said stub shaft and located between a pair of spring lock 1,577,467 3/1926 Jefiries 5116 washers, each said lock washer being formed with opposed 1,777,915 10/ 1930' Douglas 51168 lugs bent at right angles to the body thereof for friction- 2,526,208 10/1950 Dowick 5116R ally engaging the side face of said grinding disc, a common 2,544,096 3/1951 Laughlin 51168 flat washer being positioned adjacent the outer spring 5 2,712,205 7/1955 Valette 51168 lock washer and a thumb screw threadingly engaged in the end of said shank of said stub shaft firmly compressing FOREIGN PATENTS the assembly to prevent said grinding disc from rotating 622,303 11/1935 Germany 51 168 freely.

References clted 1o WILLIAM R. ARMSTRONG, PrimaryExaminer UNITED STATES PATENTS 626,962 6/1899 Bird 51---168 US 835,586 11/1906 Wahlquist 51168 51168 972,575 10/1910 Schramm 51168 

